Simple answer is to add it your soils and that’s where it will stay for potentially thousands of years.

Complex answer, I personally believe Biochar shouldn’t be applied into or onto soils of any type, not with out some sort of post processing, by this I mean composting it or adding it into compost teas, I will cover both of these topics in detailed  later posts.

Why compost it? This is where an understanding of Biochar’s structure needs to be explained, think of Biochar as a sponge which will soak up nutrients and biological life into it’s millions of tiny surface pores. Biochar can be up to 95% carbon which means it structure is not susceptible to deterioration when added to compost systems, it will not rot of soften when left sitting in compost tea for months on end.

The reason for adding Biochar to your soils is all about structure, the outer surface of Biochar is where all the action happens, so reducing the size of your Biochar chunks will increase the overall surface area of your Biochar creating more tiny surface pores and micro organism habitat.

So after a few weeks or months of composting or soaking you will have a compost bin full of tiny Biochar sponges saturated with biological life and nutrient bound in humus which is the final earthy smelling product of a quality compost.

Why can’t you just add it to finished compost or to an off the shelf product like composted cow or sheep manure when you want to use it, you can do that but this is an inferior process compared to layering Biochar though a compost and letting it naturally absorb the biological life that run rampant in well made composts.

What will happen if I don’t apply it to composts and just add it straight into soils?

Dry Biochar is quite light weight and will float in water for at least 7 days or more before sinking, so your Biochar could get washed away or even blown away if it’s applied on top of you soil, If you dig it in or plough it in without processing you are adding a mass of empty sponges to your soil so chances are that Biochar will take up to 12 months before it soaks up enough goodness to become useful, but in that 12 months it could be stealing moisture and nutrients from your plants, a similar type of effect called nitrogen draw down is created when adding high carbon woody mulch to soils.